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  1. Standard member uzless
    The So Fist
    19 Oct '11 21:44
    Someone explain this in laymens terms? This thing is actually floating!

    http://futureoftech.msnbc.msn.com/_news/2011/10/19/8398355-video-wows-with-quantum-levitation
  2. Standard member sonhouse
    Fast and Curious
    20 Oct '11 02:36
    Originally posted by uzless
    Someone explain this in laymens terms? This thing is actually floating!

    http://futureoftech.msnbc.msn.com/_news/2011/10/19/8398355-video-wows-with-quantum-levitation
    It's like a piece of paper with knotted threads sticking through, the knots hold it in place. The magnetic lines from the magnet are trapped inside in small spaces and the superconductive material around it forces the lines to be in only a few places penetrating the layer so it sticks in one place like knotted threads would hold a piece of cloth. In the case of cloth, the knots are on the outside but in the superconductor, the lines are held tightly inside and pinched together so it can levitate. Don't know how much weight it could carry but it might lead to new kinds of levitating trains.
  3. 20 Oct '11 03:53
    Originally posted by sonhouse
    It's like a piece of paper with knotted threads sticking through, the knots hold it in place. The magnetic lines from the magnet are trapped inside in small spaces and the superconductive material around it forces the lines to be in only a few places penetrating the layer so it sticks in one place like knotted threads would hold a piece of cloth. In the cas ...[text shortened]... Don't know how much weight it could carry but it might lead to new kinds of levitating trains.
    I wonder how he is touching that -301 F disk without burning himself?

    Probably not very practical at those tempreatures.
  4. Standard member Soothfast
    0,1,1,2,3,5,8,13,21,
    20 Oct '11 19:26
    Originally posted by mlprior
    I wonder how he is touching that -301 F disk without burning himself?

    Probably not very practical at those tempreatures.
    Just a typical December day in Pennsylvania.
  5. Subscriber WoodPush
    Pusher of wood
    21 Oct '11 22:08 / 1 edit
    Originally posted by mlprior
    Probably not very practical at those tempreatures.
    Actually, there are already applications in use today, as I understand it. JR-Maglev uses superconducting magnetic coils for levitation.

    http://en.wikipedia.org/wiki/JR%E2%80%93Maglev

    Not really an expert on this, but I don't really think this video is much new, just a cool viral video (?)
  6. 21 Oct '11 23:09
    Originally posted by WoodPush
    Actually, there are already applications in use today, as I understand it. JR-Maglev uses superconducting magnetic coils for levitation.

    http://en.wikipedia.org/wiki/JR%E2%80%93Maglev

    Not really an expert on this, but I don't really think this video is much new, just a cool viral video (?)
    Certainly it is potentially practical to use superconductors that have to be cryogenically cooled.

    Particularly 'high temp' superconductors that only need to be cooled with liquid nitrogen rather than liquid helium.


    However this is not the same kind of thing as they use on maglev trains.

    The standard way you levitate a superconductor in a magnetic field involves eddy currents and inducing an opposing
    magnetic field.

    This is different, and potentially more useful.
  7. Standard member sonhouse
    Fast and Curious
    22 Oct '11 00:55
    Originally posted by mlprior
    I wonder how he is touching that -301 F disk without burning himself?

    Probably not very practical at those tempreatures.
    I work with liquid nitrogen in our lab all the time and you can touch stuff at that temp if you only do it for a fraction of a second like they are in the vid. Stick your finger in a bottle of LN2 and you are asking for trouble. It's all in the timing. The interesting thing I saw in that vid was the stacking of wafers with no interference with each other. That would bode well for applications that need weight bearing like trains. The problem there would be the magnetic field strength would quickly dissipate going up away from the main field so there would be a limit to how many you could stack on top of one another. Still, it will be interesting to see real apps from this.
  8. 22 Oct '11 07:26
    I don't think it would work for trains (on its own). The problem is that it has no mechanism for controlling the height above the surface. Whatever height you put it at, it stays there. So if the train gets pushed down, there is nothing to push it up again. However, with the addition of some other magnets for control, it might be useful. I guess its a question of which method uses more power, magnetic repulsion/attraction, or this method.
  9. 22 Oct '11 11:59
    Originally posted by twhitehead
    I don't think it would work for trains (on its own). The problem is that it has no mechanism for controlling the height above the surface. Whatever height you put it at, it stays there. So if the train gets pushed down, there is nothing to push it up again. However, with the addition of some other magnets for control, it might be useful. I guess its a question of which method uses more power, magnetic repulsion/attraction, or this method.
    Well the (possible) advantage I see with this is that it has the potential to use permanent
    magnates for levitation and electromagnets for propulsion, thus massively reducing the
    power requirements.

    However as sonhouse said the deciding factor is going to be how many of these can be
    put in a stack before you hit diminishing returns, and thus how much load it can support.
  10. 22 Oct '11 14:43
    Originally posted by googlefudge
    However this is not the same kind of thing as they use on maglev trains.

    The standard way you levitate a superconductor in a magnetic field involves eddy currents and inducing an opposing magnetic field.

    This is different, and potentially more useful.
    Then again, the standard way can be demonstrated using frogs, which is much cooler. I used to have a video of that, but I've lost the link.

    Richard
  11. Standard member sonhouse
    Fast and Curious
    22 Oct '11 15:52 / 1 edit
    Originally posted by Shallow Blue
    Then again, the standard way can be demonstrated using frogs, which is much cooler. I used to have a video of that, but I've lost the link.

    Richard
    Yeah, the frog thing certainly works but I think the gauss rating of the magnet in question was approaching 100,000, a significantly powerful magnet. Any kind of metal on your person would tend to be ripped out of your pockets in that kind of field, except the non-magnetic kind but still, if you forgot and had some kind of steel on your person, or a credit card or something with a hard drive in it, you can forget reading data again.

    The real question is when in the heck are they going to get to room temperature superconductors? Been waiting for that one, along with a lot of other people, of course.

    The applications that would appear, for instance, if the wafer method was usable at room temps....
  12. 22 Oct '11 17:34
    Originally posted by googlefudge
    Well the (possible) advantage I see with this is that it has the potential to use permanent
    magnates for levitation and electromagnets for propulsion, thus massively reducing the
    power requirements.
    Why cant permanent magnets be used for levitation for normal maglevs?
  13. Standard member sonhouse
    Fast and Curious
    22 Oct '11 19:20 / 1 edit
    Originally posted by twhitehead
    Why cant permanent magnets be used for levitation for normal maglevs?
    They can and are, it's just that they weigh a ton, superconductors cut way down on weight even adding the needed cooling supply and attendant hoses. Actually, for a train they would weigh a lot more than a ton. In my work with ion implanters, they have mass analysis magnets that only produce a few thousand gauss and each one of those puppies comes in at 3000 pounds, almost 2000 Kg. You don't want to drop one on your toes

    And, that is only the magnet, the frigging power supply comes in at about 200 pounds, about 100 Kg all by itself. I would imagine one for a train would take a lot more power than an ion implanter mass analysis unit. The nice thing about the train thing is the same levitation system is used for propulsion, levitation combined with a linear motor, which is kind of like a regular motor with the windings in the rotor assembly all laid out in a line instead of a circle and it makes for propulsion.
  14. 24 Oct '11 18:03
    Originally posted by Shallow Blue
    Then again, the standard way can be demonstrated using frogs, which is much cooler. I used to have a video of that, but I've lost the link.

    Richard
    It's easily found on YouTube; just search for "levitating frog". Interestingly, the man behind this frog experiment was Andre Geim, last year's Physics Nobel Prize winner, making him the first person to win both the Ig Nobel Prize (for the frog thing) and the real Nobel Prize.
  15. Standard member sonhouse
    Fast and Curious
    25 Oct '11 01:09
    Originally posted by KazetNagorra
    It's easily found on YouTube; just search for "levitating frog". Interestingly, the man behind this frog experiment was Andre Geim, last year's Physics Nobel Prize winner, making him the first person to win both the Ig Nobel Prize (for the frog thing) and the real Nobel Prize.
    Really? He won the Ignoble prize too? He must have had a good laugh over that one.